MDCalc

NIH Stroke Scale/Score (NIHSS)

Quantifies stroke severity and monitors for neurological changes over time.

The NIH Stroke Scale has many caveats buried within it. If your patient has prior known neurologic deficits e.g. prior weakness, hemi- or quadriplegia, blindness, etc. or is intubated, has a language barrier, etc., it becomes especially complicated. In those cases, consult the NIH Stroke Scale website. MDCalc's version is an attempt to clarify many of these confusing caveats, but cannot and should not be substituted for the official protocol.

Rules:

  • Score what you see, not what you think.
  • Score the first response, not the best response (except Item 9 - Best Language).
  • Don’t coach.
1A: Level of consciousness
May be assessed casually while taking history
1B: Ask month and age
1C: 'Blink eyes' & 'squeeze hands'
Pantomime commands if communication barrier
2: Horizontal extraocular movements
Only assess horizontal gaze
3: Visual fields
4: Facial palsy
Use grimace if obtunded
5A: Left arm motor drift
Count out loud and use your fingers to show the patient your count
5B: Right arm motor drift
Count out loud and use your fingers to show the patient your count
6A: Left leg motor drift
Count out loud and use your fingers to show the patient your count
6B: Right leg motor drift
Count out loud and use your fingers to show the patient your count
7: Limb Ataxia
FNF/heel-shin
8: Sensation

9: Language/aphasia

Describe the scene; name the items; read the sentences (see Evidence)
10: Dysarthria
Read the words (see Evidence)
11: Extinction/inattention

Result:

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Advice
  • Consult Neurology immediately (if available) for all patients presenting with ischemic stroke.
  • Evaluate whether the patient is a potential candidate to receive intravenous thrombolysis (tPA).
  • Consider further imaging including CT, CT angiography and MRI/MRA.
Management

In patients who present with symptoms concerning for ischemic stroke:

  • Consult Neurology.
  • Determine the onset of stroke symptoms (or time patient last felt or was observed normal).
  • Obtain a stat head CT to evaluate for hemorrhagic stroke.
  • In appropriate circumstances and in consultation with both neurology and the patient, consider IV thrombolysis for ischemic strokes in patients with no contraindications.
  • Always consider stroke mimics in the differential diagnosis, especially in cases with atypical features (age, risk factors, history, physical exam), including:
    • Recrudescence of old stroke from metabolic or infectious stress.
    • Todd’s paralysis after seizure.
    • Complex migraine.
    • Pseudoseizure, conversion disorder.
Critical Actions
  • The NIHSS is broadly predictive of clinical outcomes, but it is important to recognize that individual cases will vary and that management decisions must be made in consultation with the patient whenever possible.
  • Patients with a score of <4 are highly likely to have good clinical outcomes.
  • Whenever possible, patients with acute stroke should be transferred to a stroke center for their initial evaluation and treatment, as the holistic care (medical optimization, early initiation of PT and OT, patient and family education and discharge planning) is associated with improved clinical outcomes; some argue that most of the gains in stroke morbidity and mortality are due to these improvements in stroke care.
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